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Re: Statistics Question

"J. Manor" wrote:

A student asked me this today and I need some help. Suppose you roll
two dice until you get a sum of 11. The probability you will get a sum
of 11 for the first time on the third roll is? Can you help us?

I think that the answer is P=0.0495, or P=(1-p)*(1-p)*p, where p is the
probability of getting 11 in any given roll (p=2/36=1/18 because two out
of 36 possible outcomes produce 11). The (1-p) is the probability of NOT
getting 11 on any given roll. You must not get 11 twice and then get it
on the third roll.